<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item v-for="(item,index)  in levelList" :key="item.path" v-if='item.meta.title'>
        <span v-if='item.redirect==="no_redirect"||index===levelList.length-1' class="no-redirect">{{item.meta.title}}</span>
        <router-link v-else :to="item.redirect||item.path">{{item.meta.title}}</router-link>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script type="text/ecmascript-6">
export default {
  created() {
    this.getBreadcrumb()
  },
  data() {
    return {
      levelList: null
    }
  },
  watch: {
    $route() {
      this.getBreadcrumb()
    }
  },
  methods: {
    getBreadcrumb() {
      // $route.matched
      // 数组，包含当前匹配的路径中所包含的所有片段所对应的配置参数对象。
      let matched = this.$route.matched.filter(item => item.name)
      // 返回有name的路由
      const first = matched[0]
      if (first && first.name !== 'dashboard') {
        matched = [{ path: '/dashboard', meta: { title: '首页' } }].concat(
          matched
        )
      }
      this.levelList = matched
    }
  }
}
</script>

<style scoped lang="stylus" rel="stylesheet/stylus">
.app-breadcrumb.el-breadcrumb
  display inline-block
  font-size 14px
  line-height 60px
  .no-redirect
    color #97a8be
    cursor text
</style>
